杨柳青,徐骏,刘国钧,Fan Z

• 1:北京有色金属研究总院
• 2:布鲁内尔大学

摘要(Abstract)：

以AZ91D镁合金为试验材料,采用双螺旋半固态浆料制备装置,研究了在液相线附近施加不同搅拌速度时,镁合金熔体凝固过程中非枝晶组织的形成机理及演变特征。结果表明:搅拌温度为605℃,搅拌速度950 r/min时,坯料组织中初生α-Mg变得细小圆整,主要以球状晶为主,由于强烈的搅拌使得熔体内部温度场与浓度场均匀,有利于晶核生长成球状;搅拌温度为590℃时,在较低的搅拌速度下就可以观察到球状初生α-Mg晶粒,且随着搅拌速度的提高,组织中初生α-Mg数量增多,晶粒逐渐变得细小、圆整,主要由于搅拌速度的增大对球晶的生长起到了抑制作用。

关键词(KeyWords)： AZ91D镁合金;双螺旋;搅拌速度;非枝晶组织

Abstract:

Keywords:

基金项目(Foundation): 国际科技合作计划项目(2009DFB50210)

作者(Author): 杨柳青,徐骏,刘国钧,Fan Z

DOI: 10.13289/j.issn.1009-6264.2012.10.018

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